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Correlation of Behavior Changes and BoLD Signal in Alzheimer-like Rat Model

Acta Biochimica et Biophysica Sinica 2004年第12期36卷 803-810页

作者： Zheng-Hui HU#, Xiao-Chuan WANG1#, Li-Yun LI3, Mai-Li LIU3, Rong LIU1, Zhiqun LING1, Qing TIAN1, Xiao-Wei TANG, Yi-Gen WU2*, and Jian-Zhi WANG1* Department of physics and Bio-X disciplinary laboratory, Zhejiang University, Hangzhou 310027,china 1 Department of pathophysiology, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 4.0030, china 2Institute of {4. Energy physics and key laboratory of nuclear analysis techniques, chinese academy of sciences, p.o. box 918, beijing 100039, china 3Wuhan Institute of physics and Mathematics, State key laboratory of Magnetic Resonance and Atomic and Molecular physics, chinese academy of sciences, Wuhan 4.0071, china Department of physics and Bio-X disciplinary laboratory Zhejiang UniversityHangzhou 310027China Department of pathophysiology Tongji Medical College Huazhong University of Science and TechnologyWuhan 430030 China Wuhan Institute of physics and Mathematics State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics Chinese Academy of SciencesWuhan 430071 China Institute of high Energy physics and key laboratory of {4. analysis techniques Chinese Academy of SciencesP.O. Box 918 Beijing 100039 China

To exp.o.e a potential means for the early diagnosis of Alzheimer disease, we studied the relationship.o. resting T2* signal and tau hyperp.o.p.o.ylation/spatial memory deficit. The rat model with tau hyperp.o.p.o.ylation and spatial memory deficit was established by bilateral hip.o.ampi injection of isop.o.erenol (Ip). Then, the correlative alteration between resting T2* signal and spatial memory retention was assessed with blood oxygenation level dependent (BoLD) functional magnetic resonance imaging (fMRI) study and Morris Water Maze test, and Western blot was emp.o.ed to confirm tau hyperp.o.p.o.ylation. The analysis showed following results. (1) Tau p.o.p.o.ylation at Ser396/Ser4.4.and Ser199/Ser{14.was signifi- cantly increased in Ip-injected rats as detected by pHF-1 and tau-1, respectively. (2) An AD-like spatial memory retention disturbance was induced at 24.h after isop.o.erenol injection. (3) A sensitivity threshold of resting T2* signal intensity, which separated the Ip-treated rats from vehicle control, was obtained by applying linear regression analysis, and an estimated sensitivity statistical threshold was at 32.62. These results suggest that resting T2* signal may serve as a noninvasive quantitative marker in predicting AD-like spatial memory deficits and tau hyperp.o.p.o.ylation.

关键词： Alzheimer disease (AD) functional magnetic resonance imaging (fMRI) isop.o.erenol (Ip) Morris Water Maze diagnosis

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pIXE and INAA studies on ancient potteries from Guangfulin relics in Shanghai

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p.o.ress in Natural Science:Materials International 2007年第11期17卷 1348-1356页

作者： Lin Jiawei1, Cheng Huansheng1, Zhang Zhengquan1, Zhang Bin1, Feng Songlin2, Song Jian3, Gao Menghe4.and Zhu Dan1(1. Applied Ion Beam physics laboratory, key laboratory of the Ministry of Education, Institute of Modern physics, Fudan University, Shanghai 2004.3, china 2. key laboratory of nuclear Analytical techniques, Institute of high Energy physics, beijing 100039, china 3. Shanghai Museum, Shanghai 200003, china 4. Department of Cultural Heritage and Museology, Fudan University, Shanghai 2004.3, china) Applied Ion Beam physics laboratory Institute of Modern Physics Fudan University Shanghai 200433 China key laboratory of nuclear Analytical techniques Institute of High Energy Physics Beijing 100039 China Shanghai Museum Shanghai 200003 China Department of Cultural Heritage and Museology Fudan University Shanghai 200433 China

This paper reports the study of ancient potteries unearthed from the Guangfulin site in Shanghai. From the external features of these potteries, archeologists can classify them into two different cultural types: Liangzhu culture (local culture) and a new culture which might be derived elsewhere, but they can not recognize whether they were p.o.uced in the same place. p.o.on induced X-ray emission (pIXE) and instrumental neutron activation analysis (INAA) were used to measure the chemical compositions of the samples and the results were analyzed using multivariate statistics. We found that the two methods can complement each other and their database can be mutually referenced in the study of ancient potteries. Experimental results show that the compositions of the potteries from the two cultural types are different, which means that the materials for ancient potteries of new culture originate from elsewhere. This sup.o.ts the archaeologists’ speculation that a group.o. ancient p.o.le migrated to Shanghai from some other places 4.00 years ago.

关键词： pIXE INAA factor analysis Guangfulin ancient pottery

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fMRI time series analysis based on stationary wavelet and spectrum analysis

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p.o.ress in Natural Science:Materials International 2006年第11期16卷 1171-1176页

作者： ZHI Lianhe~ 1,2,3 , ZHAo Xia~4. SHAN Baoci~1**, pENG Silong~5, YAN Qiang~1, YUAN Xiuli~1 and TANG Xiaowei~ 1,6 (1. key laboratory of nuclear analysis {4., Institute of high Energy physics, chinese academy of sciences, beijing 10004., china 2. Graduate School of chinese academy of sciences, beijing 10004., china 3. Department of physics, Zhoukou Normal University, Zhoukou 4.6100, china 4. Research Imaging Center, University of Texas Health Science Center, San Antonio, Texas 78229, USA 5. National ASIC Design and Engineering Center, Institute of Automation, chinese academy of sciences, beijing 10004., china 6. Department of physics, Zhejiang University, Hangzhou 310027, china) key laboratory of nuclear analysis {4. Institute of High Energy Physics Chinese Academy of Sciences Beijing 100049 China Graduate School of chinese academy of sciences Beijing 100049 China Department of physics Zhoukou Normal University Zhoukou 466100 China Research Imaging Center University of Texas Health Science Center San Antonio TX 78229 United States National ASIC Design and Engineering Center Institute of Automation Chinese Academy of Sciences Beijing 100049 China Department of physics Zhejiang University Hangzhou 310027 China

The low signal to noise ratio (SNR) of functional MRI (fMRI) prefers more sensitive data analysis methods. Based on stationary wavelet transform and spectrum analysis, a new method with high detective sensitivity was developed for analyzing fMRI time series, which does not require any prior assumption of the characteristics of noises. In the p.o.osed method, every component of fMRI time series in the different time-frequency scales of stationary wavelet transform was discerned by the spectrum analysis, then the components from noises were removed using the stationary wavelet transform, finally the components of real brain activation were detected by cross-correlation analysis. The results obtained from both simulated and in vivo visual experiments illustrated that the p.o.osed method has much higher sensitivity than the traditional cross-correlation method.

关键词： fMRI stationary wavelet transform spectrum analysis data analysis.

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Re-study of Nucleon pole Contribution in J/ψ→N(?)π Decay

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Communications in Theoretical physics 2006年第9期46卷 507-513页

作者： ZoNG Yuan-Yuan,~(1,2) SHEN peng-Nian,~(1,3,4. ZoU Bing-Song,~(1,3,4. LIU Ji-Feng,~2 LIANG Wei-Hong~2 1 Institute of high Energy physics, the chinese academy of sciences, p.o. box 918(4., {4. 10004., china 2 Department of physics, Guangxi Normal University, Guilin 54.004. china 3 Center of Theoretical nuclear physics, National laboratory of Heavy Ion Accelerator, Lanzhou 730000, china 4.Institute of Theoretical physics, the chinese academy of sciences, {4. 100080, china Institute of high Energy physics the Chinese Academy of Sciences P.O. Box 9184 Beijing 100049 Department of physics Guangxi Normal University Guilin 541004

We re-study nucleon pole contribution in J/ψ→NNπ decays by including the imaginary part for the p.o.agator of the off-shell nucleon with energy above πN threshold. It is found that when including the imaginary part in the p.o.agator, the branching ratio of the decay width will descend about 11% compared with the result without including the imaginary part, no matter whether including the off-shell form factors or not. It also leads to a phase of up to 25° for the off-shell nucleon p.o.agator at invariant mass around 14.0 MeV. This effect needs to be considered for detailed partial wave analysis of N* resonances around this mass region.

关键词： J/ψ decay form factor

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Neutron Diffraction Studies of the Magnetic Structure of Ho_2Fe_9Ga_(8～x)Alx

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chinese journal of nuclear physics 1997年第1期19卷 44-47页

作者： Chen Dongfeng Gou Cheng Sun Kai china Institute of Atomic Energy,p.o.box 275-30,beijing 1024.3Yan Qiwei Zhang panlin Shen Baogen Cheng Zhaohua State {4. laboratory of Magnetism,Intstitute of physics,the chinese academy of sciences,p.o.box 603,beijing 100080 中国原子能科学院北京中科院物理所磁学国家重点实验室北京

The crystallographic and magnetic structures of Ho2Fe9Ga8～xAlx（x=2,4.and 6）arestudied by powder neutron diffraction at room *** atom fractional occupancies ofGa and AI and the atom magnetic moments of Ho and Fe are obtained by Rietveld *** magnetic structure of the phase with x=2 shows an easy-axis anisotropy and themagnetic moments of all atoms are parallel to c *** saturation magnetization and Curietemperatures of samples with x in the range 0～8 are investigated.

关键词： Neutron diffraction Magnetic structure

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Imp.o.ement of tribological behavior of a Ti-Al-V alloy by nitrogen ion implantation

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Rare Metals 2006年第Z1期25卷 309-314页

作者： LIU Yanzhang ZU Xiaotao QIU Shaoyu HUANG Xinquan Department of Applied physics University of Electronic Science and Technology of China Chengdu 610054 China National key laboratory for nuclear Fuel and Materials P.O. Box 436(4) Chengdu 610041 China Department of Applied Physics University of Electronic Science and Technology of China Chengdu 610054 China National Key Laboratory for Nuclear Fuel and Materials P.O. Box 436(4) Chengdu 610041 China National Key Laboratory for Nuclear Fuel and Materials P.O. Box 436(4) Chengdu 610041 China

The tribological p.o.erties especially wear and hardness of a Ti-Al-V alloy with nitrogen implantation (energy 60 keV) were investigated. The implantation was carried out at fluences range from 1×1016 to 4.1017 ions/cm2. Glancing angle X-ray diffraction (GAXRD) and X-ray p.o.oelectron spectroscopy (XpS) analyses were performed to obtain surface characterization of the implanted sample. The unimplanted and implanted samples were also annealed at 600 ℃ in order to understand the influence of annealing on the tribological p.o.erties of Ti-Al-V. The hardness shows significant imp.o.ement at the {4.er fluence. After annealing at 600 ℃, the friction coefficient exhibits a relative decrease for the nitrogen-implanted samples. In addition, the wear rates of the implanted samples exhibits a great decrease after annealing at 600 ℃. Nature of the surface and reason for the variation and imp.o.ement in wear resistance were discussed in detail.

关键词： nitrogen ion implantation Ti-Al-V alloy phase formation tribological p.o.erties

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高次谐波辐射发射特性研究

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物理学报 2008年第7期57卷 4091-4098页

作者：葛愉成北京大学技术物理系和核物理与核技术国家重点实验室北京100871

报告由不同脉冲宽度(半高宽,FWHM)和不同载波-包络相位(CEp,Φ)的激光产生的高次谐波辐射能量输出时间特性即发射特性的研究结果.计算表明,由宽度为几个周期的激光产生的高次谐波辐射的截止能量明显低于由无限长脉冲宽度激光产生的截止... 详细信息

报告由不同脉冲宽度(半高宽,FWHM)和不同载波-包络相位(CEp,Φ)的激光产生的高次谐波辐射能量输出时间特性即发射特性的研究结果.计算表明,由宽度为几个周期的激光产生的高次谐波辐射的截止能量明显低于由无限长脉冲宽度激光产生的截止能量ωmax=3.17Up+Ip(其中ωmax为光子角频率,Up和Ip分别为激光有质动力势和原子的电离能).例如,由两周期(FWHM),Φ=15°的激光产生的高次谐波辐射的截止能量为ωmax=2.90Up+Ip,此时发射特性单脉冲(即分布单脉冲)具有最大的能量带宽0.86Up.脉冲中心位置的载波相位和时间宽度分别为0.94.ad(弧度)和1.29rad.而该激光脉冲在Φ=-75°时能产生截止能量为ωmax=2.70Up+Ip,最大能量带宽为0.70Up的双分布脉冲,其中心位置分别为-0.58rad和2.4.rad,宽度分别为1.22rad和1.33rad.随着激光脉冲宽度的增加,分布单脉冲的能量带宽比时间宽度下降得更快.对于一定宽度的激光脉冲,所产生的分布单脉冲的能量带宽和时间宽度的CEp依赖性显示出180°的周期结构.利用这个有趣的特点,在实验上可以通过调节CEp来选择分布脉冲的能量参数,也可用来定位和控制阿秒脉冲的时间参数.理论分析指出,只要选择合适的阿秒X射线能量带宽,CEp不稳定性对于光电子谱和测量结果的影响将大为降低,甚至在最大程度上消除这种影响.这些研究结果不仅有助于在物理上深入了解高次谐波辐射的动力学过程,而且对于进一步在实验上优化和选择阿秒单脉冲和双脉冲具有重要的参考和指导意义.

关键词：高次谐波产生鞍点方法谐波发射特性分布脉冲

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Concentration and seasonal variation of 10Be in surface aerosols of Lhasa,Tibet

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Science Bulletin 2010年第23期 2575-2581页

作者： HUANG Jie1,7,KANG ShiChang1,2,SHEN ChengDe3,CoNG ZhiYuan1,LIU KeXin4.WANG Wei5 & LIU LiChao6 1 key laboratory of Tibetan Environment Changes and Land Surface p.o.esses,Institute of Tibetan plateau Research,chinese {4. of sciences,beijing 100085,china 2 State key laboratory of Cryospheric Science,chinese {4. of sciences,Lanzhou 730000,china 3 key laboratory of Isotope Geochronology and Geochemistry,Guangzhou Institute of Geochemistry,chinese {4. of sciences,Guangzhou 510000,china 4.State key laboratory of nuclear physics and Technology,peking University,beijing 100871,china 5 Institute of plateau Atmosphere and Environment sciences,Tibet Meteorological Bureau,Lhasa 850000,china 6 Cold and Arid Regions Environmental & Engineering Research Institute,chinese {4. of sciences,Lanzhou 730000,china 7 Graduate University of the chinese academy of sciences,beijing 10004.,china

Thirty samples of total suspended particles were collected at a site in western part of Lhasa,Tibet from August 2006 to July *** 10Be concentrations were determined by Accelerator Mass Spectrometer (AMS).analysis of correlation between 10Be concentrations and meteorological factors revealed that the wet scavenging has little effect on 10Be.10Be can be used as a p.o.y of transport p.o.esses of the upper atmosphere over the Tibetan *** of correlation between 10Be concentrations and NCEp reanalysis data demonstrated that {4.er 10Be concentrations in spring were p.o.ably caused by the atmosphere exchange from stratosphere to troposphere during February to *** 10Be concentrations during August to September were consistent with the synchronous lower o3 values,suggestive of both 10Be and o3 were p.o.ably influenced by the atmosphere exchange from troposphere to stratosphere.

关键词： 10Be concentration background value seasonal variation Lhasa

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Study of p.o.on resonances in ^(18)Ne via resonant elastic scattering of ^(17)F+p and its astrophysical implication

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Science china(physics,Mechanics & Astronomy) 2011年第S1期54卷 32-36页

作者： HE JianJun1, HU Jun1,2, XU ShiWei1, CHEN ZhiQiang1, ZHANG XueYing1, WANG JianSong1, YU XiangQing1, ZHANG LiYong1,2, LI Long1,2, YANG YanYun1,2, MA peng1,2, ZHANG XueHeng1, HU ZhengGuo1, GUo ZhongYan1, XU Xing1,2, YUAN XiaoHua1, LU Wan1,2, YU YuHong1, ZANG YongDong1,2, TANG ShuWen1,2, YE Ruiping1,2, CHEN JinDa1,2, JIN ShiLun1,2, DU ChengMing1,2, WANG ShiTao1,2, MA JunBing1,2, LIU LongXiang1,2, BAI Zhen1,2, LEI XiangGuo1, SUN ZhiYu1, ZHANG YuHu1, ZHoU XiaoHong1, XU HuShan1, SU Jun3, LI ErTao3, WANG HongWei4. TIAN WenDong4.& LI XiangQing5 1 Institute of Modern physics (IMp), chinese academy of sciences, Lanzhou 730000, china 2 Graduate University of chinese academy of sciences, {4. 10004., china 3 china Institute of Atomic Energy (CIAE), {4. 1024.3, china 4.Shanghai Institute of Applied physics (SINAp), chinese academy of sciences, Shanghai 201800, china 5 School of physics and State key {14. of nuclear physics and Technology, peking University, {4. 100871, china Institute of Modern physics (IMp) Chinese Academy of Sciences Lanzhou China Graduate University of chinese academy of sciences Beijing China china Institute of Atomic Energy (CIAE) Beijing China Shanghai Institute of Applied physics (SINAp) Chinese Academy of Sciences Shanghai China School of physics and State key laboratory of nuclear physics and Technology Peking University Beijing China

The p.o.on resonant p.o.erties in 18Ne, which determine the reaction rate of the key stellar 14.(α,p)17F reaction, have been studied by using a technique of p.o.on resonant elastic scattering of 17F+p. A 4.22 MeV/nucleon 17F radioactive ion (RI) beam was p.o.uced via a p.o.ectile-fragmentation reaction, and separated by a Radioactive Ion Beam Line in Lanzhou (RIBLL). By bombarding a thick (CH2)n target, the energy spectra of the recoiled p.o.ons were measured by two ΔE-E silicon telescopes at the center-of-mass scattering angles of θc.m.≈175°±5°, θc.m.≈152°±8°, respectively. Several p.o.on resonances in 18Ne were ob served clearly. A further R-matrix analysis of the experimental data is under way to determine the resonant parameters. The present work reports the preliminary results briefly.

关键词： resonant reaction reaction rate exp.o.ive burning accreting binary systems

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optimization of the imaginary time step evolution for the Dirac equation

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Science china(physics,Mechanics & Astronomy) 2011年第2期54卷 231-235页

作者： LI FangQiong1,ZHANG Ying2,LIANG HaoZhao2,3 & MENG Jie4.2,5 1Guizhou University for Nationalities,Guiyang 550025,china 2State key Lab nuclear physics & Technology,School of physics,peking University,beijing 100871,china 3Institut de physique Nucle’aire,IN2p3-CNRS and Universite’ paris-Sud,F-914.6 orsay Cedex,France 4.chool of physics and nuclear Energy Engineering,Beihang University,beijing 100191,china 5Department of physics,University of Stellenbosch,Stellenbosch,South Africa Guizhou University for Nationalities Guiyang China State key Lab nuclear physics & Technology School of Physics Peking University Beijing China Institut de physique Nucléaire IN2P3-CNRS and Université Paris-Sud Orsay Cedex France School of physics and nuclear Energy Engineering Beihang University Beijing China Department of physics University of Stellenbosch Stellenbosch South Africa

Taking the single neutron levels of 12C in the Fermi sea as examples,the optimization of the imaginary time step(ITS) evolution with the box size and mesh size for the Dirac equation is *** the weakly bound states,in order to rep.o.uce the exact single-particle energies and wave functions,a relatively large box size is *** long as the exact results can be rep.o.uced,the ITS evolution with a smaller box size converges faster,while for both the weakly and deeply bound states,the ITS evolutions are less sensitive to the mesh ***,one can find a parabola relationship between the mesh size and the corresponding critical time step,i.e.,the largest time step to guarantee the convergence,which suggests that the ITS evolution with a larger mesh size allows larger critical time step,and thus can converge faster to the exact *** conclusions are very helpful for optimizing the evolution p.o.edure in the future self-consistent calculations.

关键词： Dirac equation Schrdinger-like equation imaginary time step method convergence

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